Haynes exited the CW/DC series at the end of Season 3. The Teen Wolf alum joined Arrow as a recurring character in the second half of Season 1 and became a regular at the beginning of Season 2 with a two-year deal. He left when that contract was up.

“We’re thrilled to announce that Colton Haynes will be reprising his role as Roy Harper for a short arc on Arrow this year,” said executive producers Marc Guggenheim and Wendy Mericle. “Roy is called back to Star City to help resolve an urgent matter with high stakes for the team. His short visit turns into something surprising when he reunites with Thea and sparks a change in both of their lives that will have long-lasting consequences…”

Team Arrow has gone through its challenges recently with Black Canary, Mad Dog and Mr. Terrific all leaving the team after a big falling out with Oliver Queen/Green Arrow. Looks like Arsenal will help to fill the void.